Low-water alarm



W. S. JACKSON.

LOW WATER ALARM.

APPLICATION FILED JULY 14,1920.

1,40 ,024, I Patented Feb. 7, 1922.

2 SHEETS-SHEET I.

W. S. JACKSON.

LOW WATER ALARM. APPLICATKON FILED JULY14.|920- Patented Feb. 7, 1922';

2 SHEETS-SHEET 2.

-2 finiar i 29% 4 jizarzuys UNITED STATES.

PATENT oFF cE.

WILLIAM s. JACKSON, or'nrnenwoon, NEW- JERsEY, ssienon T0 Hummer: B. v mnrsron, or purse-anon; PENNSYLVANIA. I

Low-WA E ALAItM. I

My invention relates to low water alarmsof the type wherein fusiblemeans normally closes a steam line leading to. an, alarm signal, the fusible member melting when the temperature rises to a danger point and thereby sounding the alarm.

One of the objects of my invention 1s to provide in a low water alarm, means which is adapted not only to sound an alarm but alsoto extinguish the fire beneath the boiler.

A further object of the invention is to provide in a low water-alarm a socket'mem-v her and means thereon normally closing communication between the alarm signal. and the interior of the. boiler and between the fire box and the interior of the boiler. Under a dangerous increase in temperature both of said closing means cease to function. This opens passages. causing the. whistle to sound and the fire to be extinguished.

A further object of the invention is to provide an effective-device of such"character wherein the fusible members are interchangeable and' removable, and which device is simple, easy to operate and capable of being cheaply made. V

In carrying out this invention employ a fixture having a common passage to which the steam is lead and communicating with a passage leading to the alarm signal, and

a passage leading tofthe fire box, each of the latter passages are closed by' a fusible plug;

An important feature of my invention is to soconstruct these plugs that they may be readily removed and replaced and be interchangeable from onepassage to the other, fitting either passage equally well and without requiring accurate fitting to. prevent leakage. Y j Y a In the accompanying drawings wherein my invention is illustrated Fig. 1 isv a side elevation partly broken away showing my invention applied: toa boiler; Fig. 2 is an elevation of the socket member, the internal threads being shown in dotted lines; Fig. 3 is a section on the 1ine'3- -3 of Fig. 2, the

Specification of Letters Patent. Application filed Jul 14, 1920. seriai'zvb. 396362.

Patented. Feb.,'7, 1922.

internal plugs being shown in position; Fig.

4 is a plan and Fig. 5 an elevation of the outer plug; Fig. 6 is a plan and Fig. 7 an I and F igj 9 an elevation of a cap for the outer plug; Fig. 10 is an elevation and Fig. 11 is a plan of the fusible stopper. i 7

Referring to thedrawings a boiler of any suitable type is indicated at l, the crown sheet being shown at 5. A socket member shown at 2 is connected by a pipe 4 to a whistle 6. v

'The socket member indicated at 2 comprises. a hollow bushing like member having Y the nut 6 adjacentione? endthereof. Adja cent thei-nut, the socket shown. as provided Wdth'eXternaI tapering threads 10' and above the threaded portion a series of channelsll furnish means of. communication between the exterior of the plug and a chamber 14 within the same. Beyond the chamber the, socket may be. tapered as at 18.

A set of internal tapering threads 201may be provided adjacent theends ofthe. socket for engagement with the pipe 4. Achannel 22 leads. from the. threaded portion 20 and communicates with a double shouldered portion 23, 24 on the socket member. These shoulders are adapted-to. form seats for similar shoulders 28, 29 on a fusible member 30 adapted toxbe-seated thereon. This. fusible" member may be. made'of any suitable material and may beheld in place by a plug 40. The plug 40 has a channel 42 extending I therethrough and may have tapering threads 44 thereon, fitting similar threads on the interior of the socket 2. A suitable wrench engaging. in plug 40.

4 A second plug 50, havingan aperture'51 extending therethrough, may be secured by eans 46may-be provided on the elevation of the inner plug; Fig. 8 is a plan means of tapering threads 52 to the socket 7 member. This plug 50- may be provided with suitable wrench engaging means, in this instance shown as a squared hole, 55 forfacilitating positioning and removal thereof.

. A second fusible plugBO, which maybe ofthe same size'as the" plug 30, is adaptedto be seated adjacent one-end of the plug 50- and to be secured in place by means of acap 60 shown as threaded at 57 to the plug 50.. The cap 60 is provided with a'centr alaperture -61 aligning with the aperture in the plug 50; The'fusibleplug 30 is acircular member, comprising twoportionsZG and, 2Q

of different diameters. The portion 28 of the fusible member may seat in the aperture 61 of the cap and be centered thereby. This construction provides two shoulders which .aid in making a tight joint. The fusible plugs 30 and 30 being of the same size are interchangeable so that only the one size need be kept instock. j To assemble the device a fusible'member 30 is inserted in an empty casing and a plug 40 is threaded in the opening. 7 Another fusible member, which may be of the same dimensions as the one previouslymentioned, is seated on-a plug and is secured thereto by the cap 60. It will be noted that by 'providing the shoulders on the fusible members the latter may be more readily seated and a better bearin surface is provided, thereby assuring a tig t joint. After the plugs'have been inserted in place the case is ready to be inserted in the crown sheet of the boiler and to be connected as desired.

-When the temperature within the-boiler becomes sufiiciently hi h, the fusible members 30 and 30 are me ted, thereby opening communication through the op'enmg 11 to the-signal and to the fire box, whichwill cause the signal to be sounded and the fire to be extinguished.

Having thus described my invention,

claim: 1

1. Ina low water alarm, a socket member h'aving'alongitudinal opening therethrough,

a communicating branch passageway leading therefrom, and removable fusible plugs for 'closing said passageway at each side of the communicating branch;

2. The combination with a crown sheet of a boiler, a socket member having an opening,

therefrom, one passage leading to the fire box to direct steam onto the fire, a signal 7 of a socket member having an opening and communicating branch passageways, one of said passageways leading to the firebox to direct steam onto the fire, a signal to which the-otherof said passages lead, and fusible plugs fitting in and closing each of said passageways and adapted to melt when. the water reaches a dangerous level. j j

4. In a safety plug, comprising a socket member having a bore extending therethrough, two spaced plugs in said socket member, each having a channel therethrough nels. I

5*. In a safety plug, a socket member'having'a bore extending therethrough, two removable spaced plugs in said socket inemberfeach' havmg a channel therethrough,

communicating branch passaveways leading f and fusible means closing said chan-' and fusible means removably held bysaid, plugs to close the channels.

6. In combination with the-crown sheet 'of a boiler, a safety'plug comprising a tubu- 7 plugs, one plug being adjacent oneend and the other adjacent the other end, apertures in said plugs communicating with a central chamber and fusible means closing said apera I tures.

8. A socket member having internal plugs, one plugbeing adjacent one end and the other adjacent the other end, apertures in said plugs communicating with a central.

chamber, a channel leading from the chamher to the exterior of the plug and fusible means closing said apertures.

9; A socket member havlng threads, and having a chamber intermedlate said threads, an aperture extendingthrough the wall ofthe socket member to said chamher, two apertured plugs, each engagingone two internal 7 thread, and fusible means closing said apertures. I 7 10. A socket memberhaving two internal tapering threads, and havinga chamber between said threads, an aperture extending through the wall ofzthe socket member to said chamber, and two apertured plugs each.

engaging one thread, the apertures in said plugs being closed by fusible stoppers held against said plugs. l

11. A socket member having two internal tapering threads, and having a chamber between said threads, an aperture extending through the wall of the socket member to said chamber, and two apertured plugs each engaging one-thread, the apertures in said plugs being closed by fusible material, one of said plugs beinglarger than the other;

plug. 7

12. A socket member having three tapering threads, apertured threaded plugs adapted to engage the intermediate and one ofthe end threads, a fusible member secured in place by the apertured plug which engages the intermediate thread, a fusible member resting on the other aperturedplug, and

means for securing the last mentioned fusiblemember in place. r

13. A socket meinberhaving three threads,

,apertured threaded plugs adapted to engage the intermediate and one of the end threads, a shouldered fusible member secured within .themeinber by theapertured plug which engages the intermediate'thread, a shoulderedfusible member resting on the other aper;

tured'plug, and threaded means for securing the last mentioned fusible member in place.

14:. 'A socket member having two internal threads, a chamber intermediate, said threads,

a channel leading from said chamber to the exterior of said member, stepped shoulders Within said member,.a removable, fusible, plug seated on said shoulders, an apertured plugthreaded to one of said threads and securing said fusible member in place, a bore extending outwardly from said fusible member, a plug threaded to the other thread, a channel therethrough, a shouldered fusible member seated on said last mentioned plug, a cap engaging said shouldered member and threaded to said last mentioned plug.

15. The combination With a socket membervadapted to be applied to the crown sheet of a boiler, of a pair of fusible members removably held therein, said fusible members having the same dimensions, said fusible members closing passagewa s adapted to lead from the boiler to the re box and an alarm respectively When the casing is applied to the boiler. a

16. The combination of a socket member having an internal thread, a tubular plug threaded therein and av fusible member Seated thereon and held in place by a removable cap, said plug and cap having cooperating parts which center the plug Wlth respect to the cap, said plug, fusible member, and cap,-

forming a unit removable as a Whole, from Y said casing.

17. The combination of a socket member having an internal thread, a' tubular plug 7 threaded therein, a fusible member extending across the end of the tubular plug and having an external boss, and a cap threaded on the plug and having a hole through it- W. S. JACKSON; Witnesses: V

I FRANK B. WILDRICK, WALTER FATZUIGER. 

